The invention concerns a pad of high elasticity, whose outer edge is kidney-shaped, which has a front and a back and whose back has a stable receiver box for a pad lever and whose front is soft and pliant.
Many people have a flat nose, as do, for example, all children and Orientals. Physically, the sides and the bridge of the nose form parts of a wedge-shaped surface. According to the principles of a wedge, contact pressure multiplies as the angle is reduced. This pressure is also determined by the static as well as the dynamic weight of the eyeglasses. Static weight is produced by the weight of the eyeglass frame, the weight of the lenses, etc. Dynamic weight may be produced by air turbulence, by impact during sports and play, etc.
All of these forces must be braced by adequately esthetic pads on the skin of the nose. Esthetic because the eye area is so instrumetal in determining the identity of a person that in an otherwise excellent photograph, one need only cover up the eye area to make the individual anonymous. Proper introduction of these forces is important because the skin of the nose is thin, since the nasal bones, even in otherwise corpulent people, are situated immediately beneath it. In addition, both the nose and the skin of the nose are naturally sensitive.
These factors have led to recent efforts in using pads of certain silicon rubber of a Shore-D hardness heretofore not known in this country.
Such a pad is most effective when the surface pressure at all contact points with the skin is equal. Otherwise, pressure will be concentrated, such as by a tire which is overinflated on the inner areas, or in the case of a tire which is not sufficiently inflated on the outer areas.